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itself strikes a bright reddish-brown or light brown, according to the accuracy with which the test is 
applied. Bromine may yield a snuff brown, and iodine a dark pink or garnet. Ammoniated silver nitrate 
gives nothing in the cold ; but when heated, a pinkish colour develops, and when examined by the 
microscope under alcohols, sheaf-like crystals are seen. In the same way ammoniated sulphate of copper 
gives irregular tubes. Heat and HC1, with most of the metallic salts in addition, give a purple brown or 
puce, the antimony reaction being especially beautiful. The purple brown or puce is also obtained with 
HC1 and bichromate of potassium, while HCl and chromate of potassium give a greenish-brown HC1 and 
ferrocyanide or ferricyanide of potassium give no particular colour test. These tests require accuracy and 
experience in application, and I have repeated each one again and again. I may here remark that 
alstonine costs nearly 4s. a gramme, so that for the present it is outside the range of practical pharmacy 
and therapeutics. 
Pharmacology of Alstonine. —Although pharmacology and therapeutics are not generally discussed 
at these meetings, yet I find in old numbers of the Journal reference to these subjects at your meetings. 
Besides the aspect from which I have chiefly studied, the pharmacology of alstonine will, I believe, interest 
some of you. Let me first state my reasons for following my present line of investigation. Alstonia 
constricta has been stated to resemble both cinchona and nux vomica—in fact, occupying a position in 
therapeutics midway between the two. My experiments then were so planned that I might chance to find 
out the points of resemblance and difference to the two named drugs. 
Action on the Small Life of Pond Water and Hay Infusion. —A drop of pond water in a cell and 
kept at summer temperature was examined by the microscope and found to contain such as Closterium, 
Vorticella, Paramcecium , Amoeba, and others in active movement. Hay infusion was also placed in another 
cell and examined, and showed a field teeming chiefly with Paramoscium bounding across the field. These 
two slides were kept to compare with two similarly prepai'ed slides, to which, however, alstonine alkaloid 
in solution had been added. The slide of pond water to which has been added 1 in 6,000 alstonine bears a 
report as follows :—Movements of inhabitants much slowed in fifteen minutes, and all evidently dead in 
two hours. The animalcules appear to ingest the alstonine, and gradually die, due to coagulation of their 
protoplasm. When the alstonine is first added, it acts as a stimulant, and the inhabitants rush across the 
field with increased activity, and even the lazy Amoeba raises himself up ; but in a few seconds all is 
changed, and instead of bounding over the field the Paramcecium moves within a narrower circle, and 
more slowly, and finally dies. In Rotifera the alstonine seems first to paralyse the fine cilia. 
With hay infusion much the same results. A solution equal to 1 in 6,000 of the total mass soon 
slows the movements, and in fifteen minutes the movements are greatly slowed, and in two and a-half 
hours only two or three appear alive in a whole field, and they only move with the utmost langour and at 
long intervals. In three and a-half hours the whole field becomes lifeless. The pigment is seen collected 
in the centre, leaving a clear rim. At the end of the experiment the two slides, to which no alstonine was 
added, show their denizens alive and highly active. Alstonine then appears to act like quinine by 
coagulating the protoplasm, but in its action on amoeba, &c., it is only one quarter as toxic as quinine. 
Thus there is a sound reason for its employment in the treatment of malaria. 
On Proofs Blood. —It is so difficult to keep blood alive for any time in experiments of the kind 
presently being pursued that my experiments on blood only bear a provisional interpretation. One in 
27,000 alstonine in saline solution was found to slow very perceptibly the movements of the amoeboid cells. 
Action on Beetles. —I next desired to ascertain the action of the alkaloid on life higher than that 
found in hay infusion and ponds, and to compare it with quinine and strychnine. I selected the common 
black beetle or cockroach, as it is usually called, but in reality the churchyard beetle ( Blaps mortisaga ). 
It is a difficult matter to overcome the disgust of catching and handling this repulsive insect even to one 
well accustomed to handling frogs and toads. The insect, besides, is not easily caught unengorged, and 
that is what one wants. He is very lively, and on the first approach of danger makes for his retreat. For 
my experiments four wide-mouthed bottles were taken, well dried and provided with caps, so that plenty of 
air was admitted, and each bottle was provided with a tiny flat vessel nearly full of water. 
(1.) Contained, besides, cane sugar in powder scattered all over the bottom, for the beetle, although 
no vegetarian, dearly likes sugar or sweets of any kind. In the midst of this nectarian repast the beetle 
was planted, and at the end of four days he was evidently enjoying himself when he was killed. 
(2.) Contained 1 in 1,000 alstonine alkaloid diluted with powdered cane sugar. At the end of the 
thirty-six hours the beetle may die, but this is not always the case ; he sometimes may live two days. At 
